gas mixture

GoldenMotor.com

MatCauthon137

Member
May 12, 2009
56
0
6
Albuquerque, NM
ok, so i have been reading through the forums and enjoying my bike but here is the deal...i have seen alot of different opinions in different places about gas:oops:il mixture...i have a 48cc grubee skyhawk and have been running it at 25:1 (after break-in) and lately the power has been getting worse...i am going out now to check for air leaks and clogs and things (first chance i have had in a couple weeks)...the question then is...the directions i have say 16 to 18:1 for break-in ( i used 16:1) and 25:1 after (which is what i use now) but i see alot of people saying i should go up to something more like 40:1...the oil is Quicksilver brand premium 2-cycle outboard oil (not sure if that matters)...any opinions?...should i go to a richer mixture?...50:1 maybe?...40:1?....spr.
 

BarelyAWake

New Member
Jul 21, 2009
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Maine
"16:1" oil mix ratio isn't correct - it's generally assumed that the reason that's recommended in the so-called "instructions" included with these kits is because in China they may not have the access to the high-quality 2stroke oils we have here and may well just be mixing with low-grade motor oil... or fish oil for all we know.

I think this whole "need heavy mix for break-in" isn't true for these sloppy Chinese engines. For a brand new high-quality engine where the tolerances are SO tight as to cause excessive friction during the initial run-in, I would defo run a heavier mix... but for the lil HTs I seriously doubt it's needful. Still - it may be better to err on the side of caution... a reasonable amount of caution that is lol

From everything I've tried with my own and everything I've read here on the forum, I really do think the best bet is to simply follow the recommended mix ratio the manufacturer of the oil recommends and just make sure it's a quality one.

Should it give ya the heebie-jeebies, just add a touch more to the mix - whatever you choose to do you should defo check the plug color and peer into the cylinder and check for carbon buildup on the piston from time to time.

Works fer me (50:1 with 50:1 synthetic Amsoil 'Injector') ;)


edit: oh and BTW, you may know this but 'Quicksilver' brand is just another oil but "certified" by Mercury for marine use in their outboards... yer payin' extra for that spiffy "certification" and the privilege of being allowed to run it without voiding the warranty on an outboard you prolly haven't got :)
 
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Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
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www.sickbikeparts.com
25:1, 32:1, etc should not make any difference with a good oil. Stick with 25:1 and look elsewhere for your problem.

What kind of plug and what does it look like after a hard run?
 

MatCauthon137

Member
May 12, 2009
56
0
6
Albuquerque, NM
ok, so i am beginning to think maybe it's just me...or just the way she was designed...it runs great on flats and obviously downhill, the problem comes from trying to take her uphill. during the break in she went up the hill outside my house without any help...shortly after the break-in she stopped doing that and i had to help her up with pedals...the other day i was riding her downhill at about 21 mph and i heard a pop...kinda like a backfire...i have taken everything apart and inspected everything i can think of...nothing appears to be broken and she she still runs perfectly as long as the land is flat...but now i have to do most of the work coming up that hill that i used to have to help her up...the same hill she took by herself before i broke her in....bf.
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
1,797
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Los Angeles, CA.
Make sure your outboard oil says it can be used in 'air cooled' engines! Outboard engines are water cooled & run at lower temps, so they use different oil.

*edit* Too much oil in the gas will also lean out the gas/ air mixture!
less oil = more gas. ;)
 
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BarelyAWake

New Member
Jul 21, 2009
7,194
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Maine
"i heard a pop...kinda like a backfire"

Jus' a guess - but ya might wanna check the torque & gasket on the head... an intermittent "pop" or a backfire sound (particularly when warming up) can be a sign of a head gasket leak. Happened w/mine and I just needed to check & tighten the head bolts a touch.
 

MatCauthon137

Member
May 12, 2009
56
0
6
Albuquerque, NM
thanks, guys...i tightened the head bolts (don't have a torque wrench, so did it by hand, they were just a tad loose) and replaced the spark plug...just to check...ran her for about 10-15 min and then took the spark plug out...clean as a whistle...2 or 3 drops of oil on the southern tip is all...also oil says "Provides excellent 2-cycle lubrication for all horsepower outboards and other 2-cycle water or air-cooled engines." still no power on hills .duh.

i also think i am gonna switch to a 50:1 mixture to see what happpens, i have about half a gallon of gas left that i will use and then the next gallon i mix will be a 50:1, we will see how that works...the oil itself does not say anything about it's preferred mixture, but there is a chart on the back for different mixtures and how many ounces to add to each one...
 
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